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turn. Normally, the lead is one-half the degrees of bank.
For example, if the bank is 30°, lead the rollout by 15°. As
the wings become level, the control pressures should be
smoothly relaxed so that the controls are neutralized as the
aircraft returns to straight-and-level fl ight. As the rollout is
being completed, attention should be given to outside visual
references to determine that the wings are being leveled and
the turn stopped.
and opposes inertia (apparent centrifugal force). These two
lift components act at right angles to each other causing the
resultant total lifting force to act perpendicular to the banked
wing of the aircraft. It is the horizontal lift component that
actually turns the WSC aircraft. [Figure 6-10]
Shallow turns are accomplished by moving the control bar
to the side slightly, waiting for the wing to roll the desired
amount, and then releasing the side pressure on the control bar
back to the center position. The WSC aircraft will stabilize in
the turn with no control pressures required. During a shallow
turn there is no signifi cant increase in airspeed or G forces
that can easily be noticed by the student. [Figure 6-11] Once
a shallow turn is initiated, it is a good practice to be stabilized
at a constant bank and then exit to a predetermined heading.
To exit the shallow turn, opposite sideways pressure must
be put on the control bar to bring the WSC aircraft back to
level fl ight.
For higher banked turns, the entry speed should be well
above 1.3 times the stall speed, which increases signifi cantly
in higher banked turns. As an example, at least 1.5 times the
stall speed should be the entry speed for a 40 degree banked
turn to maintain the 1.3 times the stall speed safety margin.
Wings with a trim speed of 1.3 times the stall speed require
an increase in speed slightly. In all constant altitude, constant
airspeed turns, it is necessary to increase the angle of attack
of the wing when rolling into the turn by pushing out on
the control bar. This is required because part of the vertical
lift has been diverted to horizontal lift. Thus, the total lift
must be increased to compensate for this loss. Similarly, the
throttle must be increased to maintain the same altitude in
steeper banks.
6-10
Figure 6-11. Pilot’s view of a shallow turn with a 20° bank.
and medium banked turns. Do not exceed the bank angle
limitation in the Pilot’s Operating Handbook (POH).
The pilot’s posture while seated in the aircraft is very
important, particularly during turns. It affects the interpretation
of outside visual references. Pilots should not lean away from
the turn in an attempt to remain upright in relation to the
ground rather than ride with the aircraft. This should be a
habit developed early so that the pilot can properly learn to
use visual references.
Beginning students should not use large control applications
because this produces a rapid roll rate and allows little time
for corrections before the desired bank is reached. Slower
(small control displacement) roll rates provide more time to
make necessary pitch and bank corrections. As soon as the
aircraft rolls from the wings-level attitude, the nose should
also start to move along the horizon, increasing its rate of
travel proportionately as the bank is increased.
The following variations provide excellent guides. If the
nose moves up or down when entering a bank, excessive or
insuffi cient pitch control is being applied. During all turns,
the controls are used to correct minor variations as they are
in straight-and-level fl ight.
To understand the relationship between airspeed, bank, and
radius of turn, it should be noted that the rate of turn at any
given true airspeed depends on the horizontal lift component.
The horizontal lift component varies in proportion to the
amount of bank. Therefore, the rate of turn at a given true
airspeed increases as the angle of bank is increased. On the
other hand, when a turn is made at a higher true airspeed at a
given bank angle, the inertia is greater and the horizontal lift
component required for the turn is greater causing the turning
rate to become slower. Therefore, at a given angle of bank, a
higher true airspeed makes the radius of turn larger because
the aircraft is turning at a slower rate. [Figure 6-12]
When changing from a shallow bank to a medium bank, the
airspeed of the wing on the outside of the turn increases in
relation to the inside wing as the radius of turn decreases. The
additional lift developed because of this increase in speed of
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Weight-Shift Control Aircraft Flying Handbook(72)
